Implemented enhancements:

• Allow to add expression function providers using DI tags #711 (goetas)

Closed issues:

• Symfony 4 - Service "jms_serializer" not found #713
• Configuration property enable_cache is missing #712
• IndexBy in OneToMany Annotation is ignored #710
• why there is backslash ? #709
• Declaration must be compatible #708
• Unrecognized option "xml" under "jms_serializer.visitors" #698